Field of the Invention
The invention relates to a component for conducting or receiving a fluid, in particular a component of a fluid-conducting line system of an industrial plant, especially a line system of a tertiary cooling circuit of a nuclear power station. The invention relates, moreover, to a method for testing such a component.
The components of a fluid-conducting line system in industrial plants, for example in plants in the chemical industry or in power plants, for example the cooling lines in the tertiary cooling circuit of a nuclear power station, are often composed of underground, internally and externally rubberized steel lines or concrete pipes. Both types of pipe, however, are subject to wear due to corrosion or erosion and often have to be replaced in older nuclear power plants. Particularly in the case of nuclear power plants cooled by seawater, the corrosion of a steel line presents a serious problem, as soon as the rubberizing layer is attacked or damaged. For that reason, the components of those line systems which are composed of steel or concrete are replaced by components having a load-bearing structural element which is constructed from a glass fiber reinforced plastic, for example a composite material composed of glass fibers and epoxy resin (EP). The respective components are additionally provided both on their inside and their outside with a protective or reinforcing layer. The disadvantage of components of that type, however, is their restricted testability since commonly acceptable methods, such as for example, eddy-current testing, cannot be adopted, since they presuppose an electrically conductive material. Ultrasonic testing methods, although fundamentally possible, are nevertheless unsuitable for practical use because of the complex composite construction. At the present time, therefore, the testing of such components, which are constructed from a composite glass fiber/plastic material and which may not only be components of a line system, but also containers fillable with a fluid, is only carried out by a visual inspection, in such a way that a manipulator is inserted into the component to be tested and the inner surface of the latter is inspected with a video camera. Visual inspection is difficult, however, since the emptied components are usually wet and there are sometimes deposits, sludge and biofilm on the inner walls. Only conspicuous changes on the inner pipe wall can therefore be established by a visual inspection.